Shortly before the section of the M40 to Stokenchurch had opened in 1967, a bridge across the new motorway was the scene of a daring stunt which became the star attraction of a Thunderbird film.

The Film

The Thunderbird films were a British science-fiction television series created by Gerry and Sylvia Anderson. On TV in the 1960s they were very popular, but when made into two feature-length films for cinemas they were not considered a success, critically or financially.

Set in the 2060s the films were made using a form of electronic marionette puppetry, combined with scale-model special effects sequences.

The action followed the exploits of “International Rescue”, a life-saving organisation equipped with technologically-advanced land, sea, air and space rescue craft. These were headed by a fleet of five vehicles named the Thunderbirds and launched from the organisation’s secret base of operations in the Pacific Ocean. The main characters were ex-astronaut Jeff Tracy, leader of “International Rescue”, and his five adult sons, who pilot the Thunderbird machines, and Lady Penelope Creighton-Ward.

Lady Penelope was a world-renowned supermodel and celebrity, and had appeared on the cover of Chic magazine. She was stylish and fashionable in every aspect of her life. She was also a secret agent.

The Stunt

The Andersons when making the Thunderbirds’ films sometimes used live action shots - most commonly, showing a real human hand flicking a switch or handling a gun when a close-up was required.

For the Thunderbird 6 film a biplane, the Tiger Moth, was used for some shots.

Anderson wanted a shot of the plane flying under a motorway bridge. This was in 1967. The stretch of the M40 to Stokenchurch had just been completed, but was not yet open to the general public. Anderson’s team hatched a plan to fly the plane from Booker Airfield and under one of the bridges near Stokenchurch. They contacted all the relevant authorities but permission was refused on the grounds that it would be too dangerous. Eventually it was agreed that the plane could fly towards the bridge, land on the motorway, taxi under the bridge with the wheels safely on the ground, then take off again.

The Pilot

A highly experienced pilot called Joan Hughes was chosen to fly the plane. Joan was 49, and had started her flying career when still a teenager.

During WW2 she had been one of the “Ferry Pilots”. These were the Women Airforce Service Pilots (WASPs) who played a critical role in the deployment of airplanes. In total WASPs flew more than nine million miles in 72 different aircraft—115,000 pilot hours—for the Ferrying Division, Air Transport Command. In 1946 Joan was appointed M.B.E for her work during the war.

After the war she became one of Britain’s first female test pilots. She was also considered a capable instructor and flew all types of aircraft except flying boats.

The Action

On the appointed day, May 21, 1967, Joan travelled from her home at Foxley Grove, Holyport, near Maidenhead to Booker Airfield. There, as she climbed into the Tiger Moth biplane she became Lady Penelope, the glamorous secret agent who had never before flown an aircraft. Her mission in the film was to rescue three other characters who had had to leap onto the plane to escape from an airship which was about to disintegrate. Three dummies had therefore been fitted on the plane, to the wings, fuselage and undercarriage.

After taking off from Booker Joan would have reached the motorway bridge at Stokenchurch within only a few minutes. At 70mph she then flew straight under the bridge without touching down on the motorway and returned safely to the airfield. Mission accomplished!


However that was not the end of the matter. The authorities were upset. On March 19, 1968 at Bucks Quarter Sessions in Aylesbury Joan Hughes faced seven charges of flying dangerously, low flying, and endangering property and persons. Also prosecuted was the film production manager Norman Foster aged 39 of Cherrywood Gardens, Flackwell Heath. He faces three charges of aiding and abetting Miss Hughes. In giving her evidence Joan explained that originally she had no intention of flying under the bridge, but the weather conditions had worsened with increased turbulence. As she was about to fly under the bridge there was a very strong gust of wind which could have forced the plane onto its wingtip. This put a landing out of the question.

After hearing Miss Hughes’ evidence the jurors left the courtroom to walk half a mile to a cinema to see the film of the incident. They asked for a second viewing before they returned to consider their verdict. After a trial lasting two and a half days, the foreman of the jury announced a verdict of Not Guilty on all seven charges. They also acquitted Norman Foster of all of the three charges brought against him.

On the direction of Judge Lawrence Verney the jury then returned the same verdict for the charges against the owners of the Tiger Moth. This was Personal Plane Services Ltd of Marlow who had been accused of owning an aircraft which had been flown dangerously, and aiding and abetting. All costs were awarded to the defence.

Miss Joan Hughes and the other two parties therefore left the court without a blemish on their careers. Joan eventually retired, appropriately at Booker Airfield in 1985. She had spent over 10,000 hours instructing other pilots, amassing a total of 11,800 flight hours in her logbook.